Field of the Invention
The present invention relates to a pilot type solenoid valve including a pilot valve unit having a fixed core and a movable core, and a passage block unit formed with a valve seat which will come into or out of contact with a valve element.
Related Art
A pilot type solenoid valve for controlling fluid is used in, for example, general industrial machines such as machine tools, welding machines, fusion cutting machines, transportation machines, and air conditioning facilities.
Some of conventional pilot type solenoid valves are each provided with a diaphragm valve as a main valve element and configured to control a pressure in a back chamber of the diaphragm valve with the solenoid valve to open and close the diaphragm valve. In general, the diaphragm valve is arranged horizontally. This may require a large installation space of the pilot type solenoid valve.
In industry, there is a demand for pilot type solenoid valves each having a thickness of about 10 mm and being able to be arranged in parallel. However, such a valve is difficult to realize in practice.
On the other hand, as disclosed in Patent Document 1, the inventors of the present invention proposed that four diaphragm valve elements are arranged vertically in order to make the whole installation space compact.